Suzuki RV125 Service Manual page 71

PISTON-TO-CYLINDER CLEARANCE
Subtract the piston diameter from the cylinder bore diameter. If
the piston-to-cylinder clearance exceeds the service limit, rebore
the cylinder and use an oversize piston or replace both the cylin-
der and the piston.
$ Piston-to-cylinder clearance
Service Limit: 0.120 mm
PISTON RING GROOVE CLEARANCE
Measure the side clearance of the 1st and 2nd rings using the
thickness gauge If any of the clearances exceed the limit,
replace both the piston and piston rings.
$ Piston ring to groove clearance
Service Limit 1st : 0.18 mm
2nd : 0.15 mm
% 09900-20803: Thickness gauge
09900-20205: Micrometer (0 – 25 mm)
$ Piston ring groove width
Standard 1st and 2nd: 1.01 – 1.03 mm
Oil : 2.01 – 2.03 mm
$ Piston ring thickness
Standard 1st and 2nd: 0.970 – 0.990 mm
NOTE:
Remove any carbon from the piston crown and ring grooves
using a soft-metal scraper.
PISTON RING FREE END GAP AND PISTON RING END GAP
Measure the piston ring free end gap using a vernier calipers.
Next, fit the piston ring squarely into the cylinder and measure
the piston ring end gap using a thickness gauge.
If the piston ring's end gap is out of specification, replace the
piston ring.
$ Piston ring free end gap
Service Limit 1st : 5.8 mm
2nd : 4.0 mm
% 09900-20101: Venier calipers
$ Piston ring end gap
Service Limit 1st and 2nd: 0.7 mm
% 09900-20803: Thickness gauge
ENGINE 3-35